xref: /illumos-gate/usr/src/uts/sun4/os/trap.c (revision 88f8b78a88cbdc6d8c1af5c3e54bc49d25095c98)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <sys/mmu.h>
30 #include <sys/systm.h>
31 #include <sys/trap.h>
32 #include <sys/machtrap.h>
33 #include <sys/vtrace.h>
34 #include <sys/prsystm.h>
35 #include <sys/archsystm.h>
36 #include <sys/machsystm.h>
37 #include <sys/fpu/fpusystm.h>
38 #include <sys/tnf.h>
39 #include <sys/tnf_probe.h>
40 #include <sys/simulate.h>
41 #include <sys/ftrace.h>
42 #include <sys/ontrap.h>
43 #include <sys/kcpc.h>
44 #include <sys/kobj.h>
45 #include <sys/procfs.h>
46 #include <sys/sun4asi.h>
47 #include <sys/sdt.h>
48 #include <sys/fpras.h>
49 
50 #ifdef  TRAPTRACE
51 #include <sys/traptrace.h>
52 #endif
53 
54 int tudebug = 0;
55 static int tudebugbpt = 0;
56 static int tudebugfpe = 0;
57 
58 static int alignfaults = 0;
59 
60 #if defined(TRAPDEBUG) || defined(lint)
61 static int lodebug = 0;
62 #else
63 #define	lodebug	0
64 #endif /* defined(TRAPDEBUG) || defined(lint) */
65 
66 
67 int vis1_partial_support(struct regs *rp, k_siginfo_t *siginfo, uint_t *fault);
68 #pragma weak vis1_partial_support
69 
70 void showregs(unsigned, struct regs *, caddr_t, uint_t);
71 #pragma weak showregs
72 
73 void trap_async_hwerr(void);
74 #pragma weak trap_async_hwerr
75 
76 void trap_async_berr_bto(int, struct regs *);
77 #pragma weak trap_async_berr_bto
78 
79 static enum seg_rw get_accesstype(struct regs *);
80 static int nfload(struct regs *, int *);
81 static int swap_nc(struct regs *, int);
82 static int ldstub_nc(struct regs *, int);
83 void	trap_cleanup(struct regs *, uint_t, k_siginfo_t *, int);
84 void	trap_rtt(void);
85 
86 static int
87 die(unsigned type, struct regs *rp, caddr_t addr, uint_t mmu_fsr)
88 {
89 	struct trap_info ti;
90 
91 #ifdef TRAPTRACE
92 	TRAPTRACE_FREEZE;
93 #endif
94 
95 	ti.trap_regs = rp;
96 	ti.trap_type = type;
97 	ti.trap_addr = addr;
98 	ti.trap_mmu_fsr = mmu_fsr;
99 
100 	curthread->t_panic_trap = &ti;
101 
102 	if (type == T_DATA_MMU_MISS && addr < (caddr_t)KERNELBASE) {
103 		panic("BAD TRAP: type=%x rp=%p addr=%p mmu_fsr=%x "
104 		    "occurred in module \"%s\" due to %s",
105 		    type, (void *)rp, (void *)addr, mmu_fsr,
106 		    mod_containing_pc((caddr_t)rp->r_pc),
107 		    addr < (caddr_t)PAGESIZE ?
108 		    "a NULL pointer dereference" :
109 		    "an illegal access to a user address");
110 	} else {
111 		panic("BAD TRAP: type=%x rp=%p addr=%p mmu_fsr=%x",
112 		    type, (void *)rp, (void *)addr, mmu_fsr);
113 	}
114 
115 	return (0);	/* avoid optimization of restore in call's delay slot */
116 }
117 
118 #if defined(SF_ERRATA_23) || defined(SF_ERRATA_30) /* call ... illegal-insn */
119 int	ill_calls;
120 #endif
121 
122 /*
123  * Currently, the only PREFETCH/PREFETCHA instructions which cause traps
124  * are the "strong" prefetches (fcn=20-23).  But we check for all flavors of
125  * PREFETCH, in case some future variant also causes a DATA_MMU_MISS.
126  */
127 #define	IS_PREFETCH(i)	(((i) & 0xc1780000) == 0xc1680000)
128 
129 #define	IS_FLUSH(i)	(((i) & 0xc1f80000) == 0x81d80000)
130 #define	IS_SWAP(i)	(((i) & 0xc1f80000) == 0xc0780000)
131 #define	IS_LDSTUB(i)	(((i) & 0xc1f80000) == 0xc0680000)
132 #define	IS_FLOAT(i)	(((i) & 0x1000000) != 0)
133 #define	IS_STORE(i)	(((i) >> 21) & 1)
134 
135 /*
136  * Called from the trap handler when a processor trap occurs.
137  */
138 /*VARARGS2*/
139 void
140 trap(struct regs *rp, caddr_t addr, uint32_t type, uint32_t mmu_fsr)
141 {
142 	proc_t *p = ttoproc(curthread);
143 	klwp_id_t lwp = ttolwp(curthread);
144 	struct machpcb *mpcb = NULL;
145 	k_siginfo_t siginfo;
146 	uint_t op3, fault = 0;
147 	int stepped = 0;
148 	greg_t oldpc;
149 	int mstate;
150 	char *badaddr;
151 	faultcode_t res;
152 	enum fault_type fault_type;
153 	enum seg_rw rw;
154 	uintptr_t lofault;
155 	int instr;
156 	int iskernel;
157 	int watchcode;
158 	int watchpage;
159 	extern faultcode_t pagefault(caddr_t, enum fault_type,
160 		enum seg_rw, int);
161 
162 	CPU_STATS_ADDQ(CPU, sys, trap, 1);
163 
164 #ifdef SF_ERRATA_23 /* call causes illegal-insn */
165 	ASSERT((curthread->t_schedflag & TS_DONT_SWAP) ||
166 	    (type == T_UNIMP_INSTR));
167 #else
168 	ASSERT(curthread->t_schedflag & TS_DONT_SWAP);
169 #endif /* SF_ERRATA_23 */
170 
171 	if (USERMODE(rp->r_tstate) || (type & T_USER)) {
172 		/*
173 		 * Set lwp_state before trying to acquire any
174 		 * adaptive lock
175 		 */
176 		ASSERT(lwp != NULL);
177 		lwp->lwp_state = LWP_SYS;
178 		/*
179 		 * Set up the current cred to use during this trap. u_cred
180 		 * no longer exists.  t_cred is used instead.
181 		 * The current process credential applies to the thread for
182 		 * the entire trap.  If trapping from the kernel, this
183 		 * should already be set up.
184 		 */
185 		if (curthread->t_cred != p->p_cred) {
186 			cred_t *oldcred = curthread->t_cred;
187 			/*
188 			 * DTrace accesses t_cred in probe context.  t_cred
189 			 * must always be either NULL, or point to a valid,
190 			 * allocated cred structure.
191 			 */
192 			curthread->t_cred = crgetcred();
193 			crfree(oldcred);
194 		}
195 		type |= T_USER;
196 		ASSERT((type == (T_SYS_RTT_PAGE | T_USER)) ||
197 			(type == (T_SYS_RTT_ALIGN | T_USER)) ||
198 			lwp->lwp_regs == rp);
199 		mpcb = lwptompcb(lwp);
200 		switch (type) {
201 		case T_WIN_OVERFLOW + T_USER:
202 		case T_WIN_UNDERFLOW + T_USER:
203 		case T_SYS_RTT_PAGE + T_USER:
204 		case T_DATA_MMU_MISS + T_USER:
205 			mstate = LMS_DFAULT;
206 			break;
207 		case T_INSTR_MMU_MISS + T_USER:
208 			mstate = LMS_TFAULT;
209 			break;
210 		default:
211 			mstate = LMS_TRAP;
212 			break;
213 		}
214 		/* Kernel probe */
215 		TNF_PROBE_1(thread_state, "thread", /* CSTYLED */,
216 		    tnf_microstate, state, (char)mstate);
217 		mstate = new_mstate(curthread, mstate);
218 		siginfo.si_signo = 0;
219 		stepped =
220 		    lwp->lwp_pcb.pcb_step != STEP_NONE &&
221 		    ((oldpc = rp->r_pc), prundostep()) &&
222 		    mmu_btop((uintptr_t)addr) == mmu_btop((uintptr_t)oldpc);
223 		/* this assignment must not precede call to prundostep() */
224 		oldpc = rp->r_pc;
225 	}
226 
227 	TRACE_1(TR_FAC_TRAP, TR_C_TRAP_HANDLER_ENTER,
228 		"C_trap_handler_enter:type %x", type);
229 
230 #ifdef	F_DEFERRED
231 	/*
232 	 * Take any pending floating point exceptions now.
233 	 * If the floating point unit has an exception to handle,
234 	 * just return to user-level to let the signal handler run.
235 	 * The instruction that got us to trap() will be reexecuted on
236 	 * return from the signal handler and we will trap to here again.
237 	 * This is necessary to disambiguate simultaneous traps which
238 	 * happen when a floating-point exception is pending and a
239 	 * machine fault is incurred.
240 	 */
241 	if (type & USER) {
242 		/*
243 		 * FP_TRAPPED is set only by sendsig() when it copies
244 		 * out the floating-point queue for the signal handler.
245 		 * It is set there so we can test it here and in syscall().
246 		 */
247 		mpcb->mpcb_flags &= ~FP_TRAPPED;
248 		syncfpu();
249 		if (mpcb->mpcb_flags & FP_TRAPPED) {
250 			/*
251 			 * trap() has have been called recursively and may
252 			 * have stopped the process, so do single step
253 			 * support for /proc.
254 			 */
255 			mpcb->mpcb_flags &= ~FP_TRAPPED;
256 			goto out;
257 		}
258 	}
259 #endif
260 	switch (type) {
261 		case T_DATA_MMU_MISS:
262 		case T_INSTR_MMU_MISS + T_USER:
263 		case T_DATA_MMU_MISS + T_USER:
264 		case T_DATA_PROT + T_USER:
265 		case T_AST + T_USER:
266 		case T_SYS_RTT_PAGE + T_USER:
267 		case T_FLUSH_PCB + T_USER:
268 		case T_FLUSHW + T_USER:
269 			break;
270 
271 		default:
272 			FTRACE_3("trap(): type=0x%lx, regs=0x%lx, addr=0x%lx",
273 			    (ulong_t)type, (ulong_t)rp, (ulong_t)addr);
274 			break;
275 	}
276 
277 	switch (type) {
278 
279 	default:
280 		/*
281 		 * Check for user software trap.
282 		 */
283 		if (type & T_USER) {
284 			if (tudebug)
285 				showregs(type, rp, (caddr_t)0, 0);
286 			if ((type & ~T_USER) >= T_SOFTWARE_TRAP) {
287 				bzero(&siginfo, sizeof (siginfo));
288 				siginfo.si_signo = SIGILL;
289 				siginfo.si_code  = ILL_ILLTRP;
290 				siginfo.si_addr  = (caddr_t)rp->r_pc;
291 				siginfo.si_trapno = type &~ T_USER;
292 				fault = FLTILL;
293 				break;
294 			}
295 		}
296 		addr = (caddr_t)rp->r_pc;
297 		(void) die(type, rp, addr, 0);
298 		/*NOTREACHED*/
299 
300 	case T_ALIGNMENT:	/* supv alignment error */
301 		if (nfload(rp, NULL))
302 			goto cleanup;
303 
304 		if (curthread->t_lofault) {
305 			if (lodebug) {
306 				showregs(type, rp, addr, 0);
307 				traceback((caddr_t)rp->r_sp);
308 			}
309 			rp->r_g1 = EFAULT;
310 			rp->r_pc = curthread->t_lofault;
311 			rp->r_npc = rp->r_pc + 4;
312 			goto cleanup;
313 		}
314 		(void) die(type, rp, addr, 0);
315 		/*NOTREACHED*/
316 
317 	case T_INSTR_EXCEPTION:		/* sys instruction access exception */
318 		addr = (caddr_t)rp->r_pc;
319 		(void) die(type, rp, addr, mmu_fsr);
320 		/*NOTREACHED*/
321 
322 	case T_INSTR_MMU_MISS:		/* sys instruction mmu miss */
323 		addr = (caddr_t)rp->r_pc;
324 		(void) die(type, rp, addr, 0);
325 		/*NOTREACHED*/
326 
327 	case T_DATA_EXCEPTION:		/* system data access exception */
328 		switch (X_FAULT_TYPE(mmu_fsr)) {
329 		case FT_RANGE:
330 			/*
331 			 * This happens when we attempt to dereference an
332 			 * address in the address hole.  If t_ontrap is set,
333 			 * then break and fall through to T_DATA_MMU_MISS /
334 			 * T_DATA_PROT case below.  If lofault is set, then
335 			 * honour it (perhaps the user gave us a bogus
336 			 * address in the hole to copyin from or copyout to?)
337 			 */
338 
339 			if (curthread->t_ontrap != NULL)
340 				break;
341 
342 			addr = (caddr_t)((uintptr_t)addr & TAGACC_VADDR_MASK);
343 			if (curthread->t_lofault) {
344 				if (lodebug) {
345 					showregs(type, rp, addr, 0);
346 					traceback((caddr_t)rp->r_sp);
347 				}
348 				rp->r_g1 = EFAULT;
349 				rp->r_pc = curthread->t_lofault;
350 				rp->r_npc = rp->r_pc + 4;
351 				goto cleanup;
352 			}
353 			(void) die(type, rp, addr, mmu_fsr);
354 			/*NOTREACHED*/
355 
356 		case FT_PRIV:
357 			/*
358 			 * This can happen if we access ASI_USER from a kernel
359 			 * thread.  To support pxfs, we need to honor lofault if
360 			 * we're doing a copyin/copyout from a kernel thread.
361 			 */
362 
363 			if (nfload(rp, NULL))
364 				goto cleanup;
365 			addr = (caddr_t)((uintptr_t)addr & TAGACC_VADDR_MASK);
366 			if (curthread->t_lofault) {
367 				if (lodebug) {
368 					showregs(type, rp, addr, 0);
369 					traceback((caddr_t)rp->r_sp);
370 				}
371 				rp->r_g1 = EFAULT;
372 				rp->r_pc = curthread->t_lofault;
373 				rp->r_npc = rp->r_pc + 4;
374 				goto cleanup;
375 			}
376 			(void) die(type, rp, addr, mmu_fsr);
377 			/*NOTREACHED*/
378 
379 		default:
380 			if (nfload(rp, NULL))
381 				goto cleanup;
382 			addr = (caddr_t)((uintptr_t)addr & TAGACC_VADDR_MASK);
383 			(void) die(type, rp, addr, mmu_fsr);
384 			/*NOTREACHED*/
385 
386 		case FT_NFO:
387 			break;
388 		}
389 		/* fall into ... */
390 
391 	case T_DATA_MMU_MISS:		/* system data mmu miss */
392 	case T_DATA_PROT:		/* system data protection fault */
393 		if (nfload(rp, &instr))
394 			goto cleanup;
395 
396 		/*
397 		 * If we're under on_trap() protection (see <sys/ontrap.h>),
398 		 * set ot_trap and return from the trap to the trampoline.
399 		 */
400 		if (curthread->t_ontrap != NULL) {
401 			on_trap_data_t *otp = curthread->t_ontrap;
402 
403 			TRACE_0(TR_FAC_TRAP, TR_C_TRAP_HANDLER_EXIT,
404 				"C_trap_handler_exit");
405 			TRACE_0(TR_FAC_TRAP, TR_TRAP_END, "trap_end");
406 
407 			if (otp->ot_prot & OT_DATA_ACCESS) {
408 				otp->ot_trap |= OT_DATA_ACCESS;
409 				rp->r_pc = otp->ot_trampoline;
410 				rp->r_npc = rp->r_pc + 4;
411 				goto cleanup;
412 			}
413 		}
414 		lofault = curthread->t_lofault;
415 		curthread->t_lofault = 0;
416 
417 		mstate = new_mstate(curthread, LMS_KFAULT);
418 
419 		switch (type) {
420 		case T_DATA_PROT:
421 			fault_type = F_PROT;
422 			rw = S_WRITE;
423 			break;
424 		case T_INSTR_MMU_MISS:
425 			fault_type = F_INVAL;
426 			rw = S_EXEC;
427 			break;
428 		case T_DATA_MMU_MISS:
429 		case T_DATA_EXCEPTION:
430 			/*
431 			 * The hardware doesn't update the sfsr on mmu
432 			 * misses so it is not easy to find out whether
433 			 * the access was a read or a write so we need
434 			 * to decode the actual instruction.
435 			 */
436 			fault_type = F_INVAL;
437 			rw = get_accesstype(rp);
438 			break;
439 		default:
440 			cmn_err(CE_PANIC, "trap: unknown type %x", type);
441 			break;
442 		}
443 		/*
444 		 * We determine if access was done to kernel or user
445 		 * address space.  The addr passed into trap is really the
446 		 * tag access register.
447 		 */
448 		iskernel = (((uintptr_t)addr & TAGACC_CTX_MASK) == KCONTEXT);
449 		addr = (caddr_t)((uintptr_t)addr & TAGACC_VADDR_MASK);
450 
451 		res = pagefault(addr, fault_type, rw, iskernel);
452 		if (!iskernel && res == FC_NOMAP &&
453 		    addr < p->p_usrstack && grow(addr))
454 			res = 0;
455 
456 		(void) new_mstate(curthread, mstate);
457 
458 		/*
459 		 * Restore lofault.  If we resolved the fault, exit.
460 		 * If we didn't and lofault wasn't set, die.
461 		 */
462 		curthread->t_lofault = lofault;
463 
464 		if (res == 0)
465 			goto cleanup;
466 
467 		if (IS_PREFETCH(instr)) {
468 			/* skip prefetch instructions in kernel-land */
469 			rp->r_pc = rp->r_npc;
470 			rp->r_npc += 4;
471 			goto cleanup;
472 		}
473 
474 		if ((lofault == 0 || lodebug) &&
475 		    (calc_memaddr(rp, &badaddr) == SIMU_SUCCESS))
476 			addr = badaddr;
477 		if (lofault == 0)
478 			(void) die(type, rp, addr, 0);
479 		/*
480 		 * Cannot resolve fault.  Return to lofault.
481 		 */
482 		if (lodebug) {
483 			showregs(type, rp, addr, 0);
484 			traceback((caddr_t)rp->r_sp);
485 		}
486 		if (FC_CODE(res) == FC_OBJERR)
487 			res = FC_ERRNO(res);
488 		else
489 			res = EFAULT;
490 		rp->r_g1 = res;
491 		rp->r_pc = curthread->t_lofault;
492 		rp->r_npc = curthread->t_lofault + 4;
493 		goto cleanup;
494 
495 	case T_INSTR_EXCEPTION + T_USER: /* user insn access exception */
496 		bzero(&siginfo, sizeof (siginfo));
497 		siginfo.si_addr = (caddr_t)rp->r_pc;
498 		siginfo.si_signo = SIGSEGV;
499 		siginfo.si_code = X_FAULT_TYPE(mmu_fsr) == FT_PRIV ?
500 		    SEGV_ACCERR : SEGV_MAPERR;
501 		fault = FLTBOUNDS;
502 		break;
503 
504 	case T_WIN_OVERFLOW + T_USER:	/* window overflow in ??? */
505 	case T_WIN_UNDERFLOW + T_USER:	/* window underflow in ??? */
506 	case T_SYS_RTT_PAGE + T_USER:	/* window underflow in user_rtt */
507 	case T_INSTR_MMU_MISS + T_USER:	/* user instruction mmu miss */
508 	case T_DATA_MMU_MISS + T_USER:	/* user data mmu miss */
509 	case T_DATA_PROT + T_USER:	/* user data protection fault */
510 		switch (type) {
511 		case T_INSTR_MMU_MISS + T_USER:
512 			addr = (caddr_t)rp->r_pc;
513 			fault_type = F_INVAL;
514 			rw = S_EXEC;
515 			break;
516 
517 		case T_DATA_MMU_MISS + T_USER:
518 			addr = (caddr_t)((uintptr_t)addr & TAGACC_VADDR_MASK);
519 			fault_type = F_INVAL;
520 			/*
521 			 * The hardware doesn't update the sfsr on mmu misses
522 			 * so it is not easy to find out whether the access
523 			 * was a read or a write so we need to decode the
524 			 * actual instruction.  XXX BUGLY HW
525 			 */
526 			rw = get_accesstype(rp);
527 			break;
528 
529 		case T_DATA_PROT + T_USER:
530 			addr = (caddr_t)((uintptr_t)addr & TAGACC_VADDR_MASK);
531 			fault_type = F_PROT;
532 			rw = S_WRITE;
533 			break;
534 
535 		case T_WIN_OVERFLOW + T_USER:
536 			addr = (caddr_t)((uintptr_t)addr & TAGACC_VADDR_MASK);
537 			fault_type = F_INVAL;
538 			rw = S_WRITE;
539 			break;
540 
541 		case T_WIN_UNDERFLOW + T_USER:
542 		case T_SYS_RTT_PAGE + T_USER:
543 			addr = (caddr_t)((uintptr_t)addr & TAGACC_VADDR_MASK);
544 			fault_type = F_INVAL;
545 			rw = S_READ;
546 			break;
547 
548 		default:
549 			cmn_err(CE_PANIC, "trap: unknown type %x", type);
550 			break;
551 		}
552 
553 		/*
554 		 * If we are single stepping do not call pagefault
555 		 */
556 		if (stepped) {
557 			res = FC_NOMAP;
558 		} else {
559 			caddr_t vaddr = addr;
560 			size_t sz;
561 			int ta;
562 
563 			ASSERT(!(curthread->t_flag & T_WATCHPT));
564 			watchpage = (pr_watch_active(p) &&
565 				type != T_WIN_OVERFLOW + T_USER &&
566 				type != T_WIN_UNDERFLOW + T_USER &&
567 				type != T_SYS_RTT_PAGE + T_USER &&
568 				pr_is_watchpage(addr, rw));
569 
570 			if (!watchpage ||
571 			    (sz = instr_size(rp, &vaddr, rw)) <= 0)
572 				/* EMPTY */;
573 			else if ((watchcode = pr_is_watchpoint(&vaddr, &ta,
574 			    sz, NULL, rw)) != 0) {
575 				if (ta) {
576 					do_watch_step(vaddr, sz, rw,
577 						watchcode, rp->r_pc);
578 					fault_type = F_INVAL;
579 				} else {
580 					bzero(&siginfo,	sizeof (siginfo));
581 					siginfo.si_signo = SIGTRAP;
582 					siginfo.si_code = watchcode;
583 					siginfo.si_addr = vaddr;
584 					siginfo.si_trapafter = 0;
585 					siginfo.si_pc = (caddr_t)rp->r_pc;
586 					fault = FLTWATCH;
587 					break;
588 				}
589 			} else {
590 				if (rw != S_EXEC &&
591 				    pr_watch_emul(rp, vaddr, rw))
592 					goto out;
593 				do_watch_step(vaddr, sz, rw, 0, 0);
594 				fault_type = F_INVAL;
595 			}
596 
597 			if (pr_watch_active(p) &&
598 			    (type == T_WIN_OVERFLOW + T_USER ||
599 			    type == T_WIN_UNDERFLOW + T_USER ||
600 			    type == T_SYS_RTT_PAGE + T_USER)) {
601 				int dotwo = (type == T_WIN_UNDERFLOW + T_USER);
602 				if (copy_return_window(dotwo))
603 					goto out;
604 				fault_type = F_INVAL;
605 			}
606 
607 			res = pagefault(addr, fault_type, rw, 0);
608 
609 			/*
610 			 * If pagefault succeed, ok.
611 			 * Otherwise grow the stack automatically.
612 			 */
613 			if (res == 0 ||
614 			    (res == FC_NOMAP &&
615 			    type != T_INSTR_MMU_MISS + T_USER &&
616 			    addr < p->p_usrstack &&
617 			    grow(addr))) {
618 				int ismem = prismember(&p->p_fltmask, FLTPAGE);
619 
620 				/*
621 				 * instr_size() is used to get the exact
622 				 * address of the fault, instead of the
623 				 * page of the fault. Unfortunately it is
624 				 * very slow, and this is an important
625 				 * code path. Don't call it unless
626 				 * correctness is needed. ie. if FLTPAGE
627 				 * is set, or we're profiling.
628 				 */
629 
630 				if (curthread->t_rprof != NULL || ismem)
631 					(void) instr_size(rp, &addr, rw);
632 
633 				lwp->lwp_lastfault = FLTPAGE;
634 				lwp->lwp_lastfaddr = addr;
635 
636 				if (ismem) {
637 					bzero(&siginfo, sizeof (siginfo));
638 					siginfo.si_addr = addr;
639 					(void) stop_on_fault(FLTPAGE, &siginfo);
640 				}
641 				goto out;
642 			}
643 
644 			if (type != (T_INSTR_MMU_MISS + T_USER)) {
645 				/*
646 				 * check for non-faulting loads, also
647 				 * fetch the instruction to check for
648 				 * flush
649 				 */
650 				if (nfload(rp, &instr))
651 					goto out;
652 
653 				/* skip userland prefetch instructions */
654 				if (IS_PREFETCH(instr)) {
655 					rp->r_pc = rp->r_npc;
656 					rp->r_npc += 4;
657 					goto out;
658 					/*NOTREACHED*/
659 				}
660 
661 				/*
662 				 * check if the instruction was a
663 				 * flush.  ABI allows users to specify
664 				 * an illegal address on the flush
665 				 * instruction so we simply return in
666 				 * this case.
667 				 *
668 				 * NB: the hardware should set a bit
669 				 * indicating this trap was caused by
670 				 * a flush instruction.  Instruction
671 				 * decoding is bugly!
672 				 */
673 				if (IS_FLUSH(instr)) {
674 					/* skip the flush instruction */
675 					rp->r_pc = rp->r_npc;
676 					rp->r_npc += 4;
677 					goto out;
678 					/*NOTREACHED*/
679 				}
680 			} else if (res == FC_PROT) {
681 				report_stack_exec(p, addr);
682 			}
683 
684 			if (tudebug)
685 				showregs(type, rp, addr, 0);
686 		}
687 
688 		/*
689 		 * In the case where both pagefault and grow fail,
690 		 * set the code to the value provided by pagefault.
691 		 */
692 		(void) instr_size(rp, &addr, rw);
693 		bzero(&siginfo, sizeof (siginfo));
694 		siginfo.si_addr = addr;
695 		if (FC_CODE(res) == FC_OBJERR) {
696 			siginfo.si_errno = FC_ERRNO(res);
697 			if (siginfo.si_errno != EINTR) {
698 				siginfo.si_signo = SIGBUS;
699 				siginfo.si_code = BUS_OBJERR;
700 				fault = FLTACCESS;
701 			}
702 		} else { /* FC_NOMAP || FC_PROT */
703 			siginfo.si_signo = SIGSEGV;
704 			siginfo.si_code = (res == FC_NOMAP) ?
705 				SEGV_MAPERR : SEGV_ACCERR;
706 			fault = FLTBOUNDS;
707 		}
708 		/*
709 		 * If this is the culmination of a single-step,
710 		 * reset the addr, code, signal and fault to
711 		 * indicate a hardware trace trap.
712 		 */
713 		if (stepped) {
714 			pcb_t *pcb = &lwp->lwp_pcb;
715 
716 			siginfo.si_signo = 0;
717 			fault = 0;
718 			if (pcb->pcb_step == STEP_WASACTIVE) {
719 				pcb->pcb_step = STEP_NONE;
720 				pcb->pcb_tracepc = NULL;
721 				oldpc = rp->r_pc - 4;
722 			}
723 			/*
724 			 * If both NORMAL_STEP and WATCH_STEP are in
725 			 * effect, give precedence to NORMAL_STEP.
726 			 * One or the other must be set at this point.
727 			 */
728 			ASSERT(pcb->pcb_flags & (NORMAL_STEP|WATCH_STEP));
729 			if (pcb->pcb_flags & NORMAL_STEP) {
730 				siginfo.si_signo = SIGTRAP;
731 				siginfo.si_code = TRAP_TRACE;
732 				siginfo.si_addr = (caddr_t)rp->r_pc;
733 				fault = FLTTRACE;
734 				if (pcb->pcb_flags & WATCH_STEP)
735 					(void) undo_watch_step(NULL);
736 			} else {
737 				fault = undo_watch_step(&siginfo);
738 			}
739 			pcb->pcb_flags &= ~(NORMAL_STEP|WATCH_STEP);
740 		}
741 		break;
742 
743 	case T_DATA_EXCEPTION + T_USER:	/* user data access exception */
744 
745 		if (&vis1_partial_support != NULL) {
746 			bzero(&siginfo, sizeof (siginfo));
747 			if (vis1_partial_support(rp,
748 			    &siginfo, &fault) == 0)
749 				goto out;
750 		}
751 
752 		if (nfload(rp, &instr))
753 			goto out;
754 		if (IS_FLUSH(instr)) {
755 			/* skip the flush instruction */
756 			rp->r_pc = rp->r_npc;
757 			rp->r_npc += 4;
758 			goto out;
759 			/*NOTREACHED*/
760 		}
761 		bzero(&siginfo, sizeof (siginfo));
762 		siginfo.si_addr = addr;
763 		switch (X_FAULT_TYPE(mmu_fsr)) {
764 		case FT_ATOMIC_NC:
765 			if ((IS_SWAP(instr) && swap_nc(rp, instr)) ||
766 			    (IS_LDSTUB(instr) && ldstub_nc(rp, instr))) {
767 				/* skip the atomic */
768 				rp->r_pc = rp->r_npc;
769 				rp->r_npc += 4;
770 				goto out;
771 			}
772 			/* fall into ... */
773 		case FT_PRIV:
774 			siginfo.si_signo = SIGSEGV;
775 			siginfo.si_code = SEGV_ACCERR;
776 			fault = FLTBOUNDS;
777 			break;
778 		case FT_SPEC_LD:
779 		case FT_ILL_ALT:
780 			siginfo.si_signo = SIGILL;
781 			siginfo.si_code = ILL_ILLADR;
782 			fault = FLTILL;
783 			break;
784 		default:
785 			siginfo.si_signo = SIGSEGV;
786 			siginfo.si_code = SEGV_MAPERR;
787 			fault = FLTBOUNDS;
788 			break;
789 		}
790 		break;
791 
792 	case T_SYS_RTT_ALIGN + T_USER:	/* user alignment error */
793 	case T_ALIGNMENT + T_USER:	/* user alignment error */
794 		if (tudebug)
795 			showregs(type, rp, addr, 0);
796 		/*
797 		 * If the user has to do unaligned references
798 		 * the ugly stuff gets done here.
799 		 */
800 		alignfaults++;
801 		if (&vis1_partial_support != NULL) {
802 			bzero(&siginfo, sizeof (siginfo));
803 			if (vis1_partial_support(rp,
804 			    &siginfo, &fault) == 0)
805 				goto out;
806 		}
807 
808 		if (nfload(rp, NULL))
809 			goto out;
810 		bzero(&siginfo, sizeof (siginfo));
811 		if (type == T_SYS_RTT_ALIGN + T_USER) {
812 			/*
813 			 * Can't do unaligned stack access
814 			 */
815 			siginfo.si_signo = SIGBUS;
816 			siginfo.si_code = BUS_ADRALN;
817 			siginfo.si_addr = addr;
818 			fault = FLTACCESS;
819 			break;
820 		}
821 		if (p->p_fixalignment) {
822 			if (do_unaligned(rp, &badaddr) == SIMU_SUCCESS) {
823 				rp->r_pc = rp->r_npc;
824 				rp->r_npc += 4;
825 				goto out;
826 			}
827 			siginfo.si_signo = SIGSEGV;
828 			siginfo.si_code = SEGV_MAPERR;
829 			siginfo.si_addr = badaddr;
830 			fault = FLTBOUNDS;
831 		} else {
832 			siginfo.si_signo = SIGBUS;
833 			siginfo.si_code = BUS_ADRALN;
834 			if (rp->r_pc & 3) {	/* offending address, if pc */
835 				siginfo.si_addr = (caddr_t)rp->r_pc;
836 			} else {
837 				if (calc_memaddr(rp, &badaddr) == SIMU_UNALIGN)
838 					siginfo.si_addr = badaddr;
839 				else
840 					siginfo.si_addr = (caddr_t)rp->r_pc;
841 			}
842 			fault = FLTACCESS;
843 		}
844 		break;
845 
846 	case T_PRIV_INSTR + T_USER:	/* privileged instruction fault */
847 		if (tudebug)
848 			showregs(type, rp, (caddr_t)0, 0);
849 		bzero(&siginfo, sizeof (siginfo));
850 		siginfo.si_signo = SIGILL;
851 		siginfo.si_code = ILL_PRVOPC;
852 		siginfo.si_addr = (caddr_t)rp->r_pc;
853 		fault = FLTILL;
854 		break;
855 
856 	case T_UNIMP_INSTR:		/* priv illegal instruction fault */
857 		if (fpras_implemented) {
858 			/*
859 			 * Call fpras_chktrap indicating that
860 			 * we've come from a trap handler and pass
861 			 * the regs.  That function may choose to panic
862 			 * (in which case it won't return) or it may
863 			 * determine that a reboot is desired.  In the
864 			 * latter case it must alter pc/npc to skip
865 			 * the illegal instruction and continue at
866 			 * a controlled address.
867 			 */
868 			if (&fpras_chktrap) {
869 			    if (fpras_chktrap(rp))
870 				goto cleanup;
871 			}
872 		}
873 #if defined(SF_ERRATA_23) || defined(SF_ERRATA_30) /* call ... illegal-insn */
874 		instr = *(int *)rp->r_pc;
875 		if ((instr & 0xc0000000) == 0x40000000) {
876 			long pc;
877 
878 			rp->r_o7 = (long long)rp->r_pc;
879 			pc = rp->r_pc + ((instr & 0x3fffffff) << 2);
880 			rp->r_pc = rp->r_npc;
881 			rp->r_npc = pc;
882 			ill_calls++;
883 			goto cleanup;
884 		}
885 #endif /* SF_ERRATA_23 || SF_ERRATA_30 */
886 		/*
887 		 * It's not an fpras failure and it's not SF_ERRATA_23 - die
888 		 */
889 		addr = (caddr_t)rp->r_pc;
890 		(void) die(type, rp, addr, 0);
891 		/*NOTREACHED*/
892 
893 	case T_UNIMP_INSTR + T_USER:	/* illegal instruction fault */
894 #if defined(SF_ERRATA_23) || defined(SF_ERRATA_30) /* call ... illegal-insn */
895 		instr = fetch_user_instr((caddr_t)rp->r_pc);
896 		if ((instr & 0xc0000000) == 0x40000000) {
897 			long pc;
898 
899 			rp->r_o7 = (long long)rp->r_pc;
900 			pc = rp->r_pc + ((instr & 0x3fffffff) << 2);
901 			rp->r_pc = rp->r_npc;
902 			rp->r_npc = pc;
903 			ill_calls++;
904 			goto out;
905 		}
906 #endif /* SF_ERRATA_23 || SF_ERRATA_30 */
907 		if (tudebug)
908 			showregs(type, rp, (caddr_t)0, 0);
909 		bzero(&siginfo, sizeof (siginfo));
910 		/*
911 		 * Try to simulate the instruction.
912 		 */
913 		switch (simulate_unimp(rp, &badaddr)) {
914 		case SIMU_RETRY:
915 			goto out;	/* regs are already set up */
916 			/*NOTREACHED*/
917 
918 		case SIMU_SUCCESS:
919 			/* skip the successfully simulated instruction */
920 			rp->r_pc = rp->r_npc;
921 			rp->r_npc += 4;
922 			goto out;
923 			/*NOTREACHED*/
924 
925 		case SIMU_FAULT:
926 			siginfo.si_signo = SIGSEGV;
927 			siginfo.si_code = SEGV_MAPERR;
928 			siginfo.si_addr = badaddr;
929 			fault = FLTBOUNDS;
930 			break;
931 
932 		case SIMU_DZERO:
933 			siginfo.si_signo = SIGFPE;
934 			siginfo.si_code = FPE_INTDIV;
935 			siginfo.si_addr = (caddr_t)rp->r_pc;
936 			fault = FLTIZDIV;
937 			break;
938 
939 		case SIMU_UNALIGN:
940 			siginfo.si_signo = SIGBUS;
941 			siginfo.si_code = BUS_ADRALN;
942 			siginfo.si_addr = badaddr;
943 			fault = FLTACCESS;
944 			break;
945 
946 		case SIMU_ILLEGAL:
947 		default:
948 			siginfo.si_signo = SIGILL;
949 			op3 = (instr >> 19) & 0x3F;
950 			if ((IS_FLOAT(instr) && (op3 == IOP_V8_STQFA) ||
951 			    (op3 == IOP_V8_STDFA)))
952 				siginfo.si_code = ILL_ILLADR;
953 			else
954 				siginfo.si_code = ILL_ILLOPC;
955 			siginfo.si_addr = (caddr_t)rp->r_pc;
956 			fault = FLTILL;
957 			break;
958 		}
959 		break;
960 
961 	case T_UNIMP_LDD + T_USER:
962 	case T_UNIMP_STD + T_USER:
963 		if (tudebug)
964 			showregs(type, rp, (caddr_t)0, 0);
965 		switch (simulate_lddstd(rp, &badaddr)) {
966 		case SIMU_SUCCESS:
967 			/* skip the successfully simulated instruction */
968 			rp->r_pc = rp->r_npc;
969 			rp->r_npc += 4;
970 			goto out;
971 			/*NOTREACHED*/
972 
973 		case SIMU_FAULT:
974 			if (nfload(rp, NULL))
975 				goto out;
976 			siginfo.si_signo = SIGSEGV;
977 			siginfo.si_code = SEGV_MAPERR;
978 			siginfo.si_addr = badaddr;
979 			fault = FLTBOUNDS;
980 			break;
981 
982 		case SIMU_UNALIGN:
983 			if (nfload(rp, NULL))
984 				goto out;
985 			siginfo.si_signo = SIGBUS;
986 			siginfo.si_code = BUS_ADRALN;
987 			siginfo.si_addr = badaddr;
988 			fault = FLTACCESS;
989 			break;
990 
991 		case SIMU_ILLEGAL:
992 		default:
993 			siginfo.si_signo = SIGILL;
994 			siginfo.si_code = ILL_ILLOPC;
995 			siginfo.si_addr = (caddr_t)rp->r_pc;
996 			fault = FLTILL;
997 			break;
998 		}
999 		break;
1000 
1001 	case T_UNIMP_LDD:
1002 	case T_UNIMP_STD:
1003 		if (simulate_lddstd(rp, &badaddr) == SIMU_SUCCESS) {
1004 			/* skip the successfully simulated instruction */
1005 			rp->r_pc = rp->r_npc;
1006 			rp->r_npc += 4;
1007 			goto cleanup;
1008 			/*NOTREACHED*/
1009 		}
1010 		/*
1011 		 * A third party driver executed an {LDD,STD,LDDA,STDA}
1012 		 * that we couldn't simulate.
1013 		 */
1014 		if (nfload(rp, NULL))
1015 			goto cleanup;
1016 
1017 		if (curthread->t_lofault) {
1018 			if (lodebug) {
1019 				showregs(type, rp, addr, 0);
1020 				traceback((caddr_t)rp->r_sp);
1021 			}
1022 			rp->r_g1 = EFAULT;
1023 			rp->r_pc = curthread->t_lofault;
1024 			rp->r_npc = rp->r_pc + 4;
1025 			goto cleanup;
1026 		}
1027 		(void) die(type, rp, addr, 0);
1028 		/*NOTREACHED*/
1029 
1030 	case T_IDIV0 + T_USER:		/* integer divide by zero */
1031 	case T_DIV0 + T_USER:		/* integer divide by zero */
1032 		if (tudebug && tudebugfpe)
1033 			showregs(type, rp, (caddr_t)0, 0);
1034 		bzero(&siginfo, sizeof (siginfo));
1035 		siginfo.si_signo = SIGFPE;
1036 		siginfo.si_code = FPE_INTDIV;
1037 		siginfo.si_addr = (caddr_t)rp->r_pc;
1038 		fault = FLTIZDIV;
1039 		break;
1040 
1041 	case T_INT_OVERFLOW + T_USER:	/* integer overflow */
1042 		if (tudebug && tudebugfpe)
1043 			showregs(type, rp, (caddr_t)0, 0);
1044 		bzero(&siginfo, sizeof (siginfo));
1045 		siginfo.si_signo = SIGFPE;
1046 		siginfo.si_code  = FPE_INTOVF;
1047 		siginfo.si_addr  = (caddr_t)rp->r_pc;
1048 		fault = FLTIOVF;
1049 		break;
1050 
1051 	case T_BREAKPOINT + T_USER:	/* breakpoint trap (t 1) */
1052 		if (tudebug && tudebugbpt)
1053 			showregs(type, rp, (caddr_t)0, 0);
1054 		bzero(&siginfo, sizeof (siginfo));
1055 		siginfo.si_signo = SIGTRAP;
1056 		siginfo.si_code = TRAP_BRKPT;
1057 		siginfo.si_addr = (caddr_t)rp->r_pc;
1058 		fault = FLTBPT;
1059 		break;
1060 
1061 	case T_TAG_OVERFLOW + T_USER:	/* tag overflow (taddcctv, tsubcctv) */
1062 		if (tudebug)
1063 			showregs(type, rp, (caddr_t)0, 0);
1064 		bzero(&siginfo, sizeof (siginfo));
1065 		siginfo.si_signo = SIGEMT;
1066 		siginfo.si_code = EMT_TAGOVF;
1067 		siginfo.si_addr = (caddr_t)rp->r_pc;
1068 		fault = FLTACCESS;
1069 		break;
1070 
1071 	case T_FLUSH_PCB + T_USER:	/* finish user window overflow */
1072 	case T_FLUSHW + T_USER:		/* finish user window flush */
1073 		/*
1074 		 * This trap is entered from sys_rtt in locore.s when,
1075 		 * upon return to user is is found that there are user
1076 		 * windows in pcb_wbuf.  This happens because they could
1077 		 * not be saved on the user stack, either because it
1078 		 * wasn't resident or because it was misaligned.
1079 		 */
1080 	    {
1081 		int error;
1082 		caddr_t sp;
1083 
1084 		error = flush_user_windows_to_stack(&sp);
1085 		/*
1086 		 * Possible errors:
1087 		 *	error copying out
1088 		 *	unaligned stack pointer
1089 		 * The first is given to us as the return value
1090 		 * from flush_user_windows_to_stack().  The second
1091 		 * results in residual windows in the pcb.
1092 		 */
1093 		if (error != 0) {
1094 			/*
1095 			 * EINTR comes from a signal during copyout;
1096 			 * we should not post another signal.
1097 			 */
1098 			if (error != EINTR) {
1099 				/*
1100 				 * Zap the process with a SIGSEGV - process
1101 				 * may be managing its own stack growth by
1102 				 * taking SIGSEGVs on a different signal stack.
1103 				 */
1104 				bzero(&siginfo, sizeof (siginfo));
1105 				siginfo.si_signo = SIGSEGV;
1106 				siginfo.si_code  = SEGV_MAPERR;
1107 				siginfo.si_addr  = sp;
1108 				fault = FLTBOUNDS;
1109 			}
1110 			break;
1111 		} else if (mpcb->mpcb_wbcnt) {
1112 			bzero(&siginfo, sizeof (siginfo));
1113 			siginfo.si_signo = SIGILL;
1114 			siginfo.si_code  = ILL_BADSTK;
1115 			siginfo.si_addr  = (caddr_t)rp->r_pc;
1116 			fault = FLTILL;
1117 			break;
1118 		}
1119 	    }
1120 
1121 		/*
1122 		 * T_FLUSHW is used when handling a ta 0x3 -- the old flush
1123 		 * window trap -- which is implemented by executing the
1124 		 * flushw instruction. The flushw can trap if any of the
1125 		 * stack pages are not writable for whatever reason. In this
1126 		 * case only, we advance the pc to the next instruction so
1127 		 * that the user thread doesn't needlessly execute the trap
1128 		 * again. Normally this wouldn't be a problem -- we'll
1129 		 * usually only end up here if this is the first touch to a
1130 		 * stack page -- since the second execution won't trap, but
1131 		 * if there's a watchpoint on the stack page the user thread
1132 		 * would spin, continuously executing the trap instruction.
1133 		 */
1134 		if (type == T_FLUSHW + T_USER) {
1135 			rp->r_pc = rp->r_npc;
1136 			rp->r_npc += 4;
1137 		}
1138 		goto out;
1139 
1140 	case T_AST + T_USER:		/* profiling or resched pseudo trap */
1141 		if (lwp->lwp_pcb.pcb_flags & CPC_OVERFLOW) {
1142 			lwp->lwp_pcb.pcb_flags &= ~CPC_OVERFLOW;
1143 			if (kcpc_overflow_ast()) {
1144 				/*
1145 				 * Signal performance counter overflow
1146 				 */
1147 				if (tudebug)
1148 					showregs(type, rp, (caddr_t)0, 0);
1149 				bzero(&siginfo, sizeof (siginfo));
1150 				siginfo.si_signo = SIGEMT;
1151 				siginfo.si_code = EMT_CPCOVF;
1152 				siginfo.si_addr = (caddr_t)rp->r_pc;
1153 				/* for trap_cleanup(), below */
1154 				oldpc = rp->r_pc - 4;
1155 				fault = FLTCPCOVF;
1156 			}
1157 		}
1158 
1159 		/*
1160 		 * The CPC_OVERFLOW check above may already have populated
1161 		 * siginfo and set fault, so the checks below must not
1162 		 * touch these and the functions they call must use
1163 		 * trapsig() directly.
1164 		 */
1165 
1166 		if (lwp->lwp_pcb.pcb_flags & ASYNC_HWERR) {
1167 			lwp->lwp_pcb.pcb_flags &= ~ASYNC_HWERR;
1168 			trap_async_hwerr();
1169 		}
1170 
1171 		if (lwp->lwp_pcb.pcb_flags & ASYNC_BERR) {
1172 			lwp->lwp_pcb.pcb_flags &= ~ASYNC_BERR;
1173 			trap_async_berr_bto(ASYNC_BERR, rp);
1174 		}
1175 
1176 		if (lwp->lwp_pcb.pcb_flags & ASYNC_BTO) {
1177 			lwp->lwp_pcb.pcb_flags &= ~ASYNC_BTO;
1178 			trap_async_berr_bto(ASYNC_BTO, rp);
1179 		}
1180 
1181 		break;
1182 	}
1183 
1184 	trap_cleanup(rp, fault, &siginfo, oldpc == rp->r_pc);
1185 
1186 out:	/* We can't get here from a system trap */
1187 	ASSERT(type & T_USER);
1188 	trap_rtt();
1189 	(void) new_mstate(curthread, mstate);
1190 	/* Kernel probe */
1191 	TNF_PROBE_1(thread_state, "thread", /* CSTYLED */,
1192 		tnf_microstate, state, LMS_USER);
1193 
1194 	TRACE_0(TR_FAC_TRAP, TR_C_TRAP_HANDLER_EXIT, "C_trap_handler_exit");
1195 	return;
1196 
1197 cleanup:	/* system traps end up here */
1198 	ASSERT(!(type & T_USER));
1199 
1200 	TRACE_0(TR_FAC_TRAP, TR_C_TRAP_HANDLER_EXIT, "C_trap_handler_exit");
1201 }
1202 
1203 void
1204 trap_cleanup(
1205 	struct regs *rp,
1206 	uint_t fault,
1207 	k_siginfo_t *sip,
1208 	int restartable)
1209 {
1210 	extern void aio_cleanup();
1211 	proc_t *p = ttoproc(curthread);
1212 	klwp_id_t lwp = ttolwp(curthread);
1213 
1214 	if (fault) {
1215 		/*
1216 		 * Remember the fault and fault address
1217 		 * for real-time (SIGPROF) profiling.
1218 		 */
1219 		lwp->lwp_lastfault = fault;
1220 		lwp->lwp_lastfaddr = sip->si_addr;
1221 
1222 		DTRACE_PROC2(fault, int, fault, ksiginfo_t *, sip);
1223 
1224 		/*
1225 		 * If a debugger has declared this fault to be an
1226 		 * event of interest, stop the lwp.  Otherwise just
1227 		 * deliver the associated signal.
1228 		 */
1229 		if (sip->si_signo != SIGKILL &&
1230 		    prismember(&p->p_fltmask, fault) &&
1231 		    stop_on_fault(fault, sip) == 0)
1232 			sip->si_signo = 0;
1233 	}
1234 
1235 	if (sip->si_signo)
1236 		trapsig(sip, restartable);
1237 
1238 	if (lwp->lwp_oweupc)
1239 		profil_tick(rp->r_pc);
1240 
1241 	if (curthread->t_astflag | curthread->t_sig_check) {
1242 		/*
1243 		 * Turn off the AST flag before checking all the conditions that
1244 		 * may have caused an AST.  This flag is on whenever a signal or
1245 		 * unusual condition should be handled after the next trap or
1246 		 * syscall.
1247 		 */
1248 		astoff(curthread);
1249 		curthread->t_sig_check = 0;
1250 
1251 		mutex_enter(&p->p_lock);
1252 		if (curthread->t_proc_flag & TP_CHANGEBIND) {
1253 			timer_lwpbind();
1254 			curthread->t_proc_flag &= ~TP_CHANGEBIND;
1255 		}
1256 		mutex_exit(&p->p_lock);
1257 
1258 		/*
1259 		 * for kaio requests that are on the per-process poll queue,
1260 		 * aiop->aio_pollq, they're AIO_POLL bit is set, the kernel
1261 		 * should copyout their result_t to user memory. by copying
1262 		 * out the result_t, the user can poll on memory waiting
1263 		 * for the kaio request to complete.
1264 		 */
1265 		if (p->p_aio)
1266 			aio_cleanup(0);
1267 
1268 		/*
1269 		 * If this LWP was asked to hold, call holdlwp(), which will
1270 		 * stop.  holdlwps() sets this up and calls pokelwps() which
1271 		 * sets the AST flag.
1272 		 *
1273 		 * Also check TP_EXITLWP, since this is used by fresh new LWPs
1274 		 * through lwp_rtt().  That flag is set if the lwp_create(2)
1275 		 * syscall failed after creating the LWP.
1276 		 */
1277 		if (ISHOLD(p))
1278 			holdlwp();
1279 
1280 		/*
1281 		 * All code that sets signals and makes ISSIG evaluate true must
1282 		 * set t_astflag afterwards.
1283 		 */
1284 		if (ISSIG_PENDING(curthread, lwp, p)) {
1285 			if (issig(FORREAL))
1286 				psig();
1287 			curthread->t_sig_check = 1;
1288 		}
1289 
1290 		if (curthread->t_rprof != NULL) {
1291 			realsigprof(0, 0);
1292 			curthread->t_sig_check = 1;
1293 		}
1294 	}
1295 }
1296 
1297 /*
1298  * Called from fp_traps when a floating point trap occurs.
1299  * Note that the T_DATA_EXCEPTION case does not use X_FAULT_TYPE(mmu_fsr),
1300  * because mmu_fsr (now changed to code) is always 0.
1301  * Note that the T_UNIMP_INSTR case does not call simulate_unimp(),
1302  * because the simulator only simulates multiply and divide instructions,
1303  * which would not cause floating point traps in the first place.
1304  * XXX - Supervisor mode floating point traps?
1305  */
1306 void
1307 fpu_trap(struct regs *rp, caddr_t addr, uint32_t type, uint32_t code)
1308 {
1309 	proc_t *p = ttoproc(curthread);
1310 	klwp_id_t lwp = ttolwp(curthread);
1311 	k_siginfo_t siginfo;
1312 	uint_t op3, fault = 0;
1313 	int mstate;
1314 	char *badaddr;
1315 	kfpu_t *fp;
1316 	struct fpq *pfpq;
1317 	uint32_t inst;
1318 	utrap_handler_t *utrapp;
1319 
1320 	CPU_STATS_ADDQ(CPU, sys, trap, 1);
1321 
1322 	ASSERT(curthread->t_schedflag & TS_DONT_SWAP);
1323 
1324 	if (USERMODE(rp->r_tstate)) {
1325 		/*
1326 		 * Set lwp_state before trying to acquire any
1327 		 * adaptive lock
1328 		 */
1329 		ASSERT(lwp != NULL);
1330 		lwp->lwp_state = LWP_SYS;
1331 		/*
1332 		 * Set up the current cred to use during this trap. u_cred
1333 		 * no longer exists.  t_cred is used instead.
1334 		 * The current process credential applies to the thread for
1335 		 * the entire trap.  If trapping from the kernel, this
1336 		 * should already be set up.
1337 		 */
1338 		if (curthread->t_cred != p->p_cred) {
1339 			cred_t *oldcred = curthread->t_cred;
1340 			/*
1341 			 * DTrace accesses t_cred in probe context.  t_cred
1342 			 * must always be either NULL, or point to a valid,
1343 			 * allocated cred structure.
1344 			 */
1345 			curthread->t_cred = crgetcred();
1346 			crfree(oldcred);
1347 		}
1348 		ASSERT(lwp->lwp_regs == rp);
1349 		mstate = new_mstate(curthread, LMS_TRAP);
1350 		siginfo.si_signo = 0;
1351 		type |= T_USER;
1352 	}
1353 
1354 	TRACE_1(TR_FAC_TRAP, TR_C_TRAP_HANDLER_ENTER,
1355 		"C_fpu_trap_handler_enter:type %x", type);
1356 
1357 	if (tudebug && tudebugfpe)
1358 		showregs(type, rp, addr, 0);
1359 
1360 	bzero(&siginfo, sizeof (siginfo));
1361 	siginfo.si_code = code;
1362 	siginfo.si_addr = addr;
1363 
1364 	switch (type) {
1365 
1366 	case T_FP_EXCEPTION_IEEE + T_USER:	/* FPU arithmetic exception */
1367 		/*
1368 		 * FPU arithmetic exception - fake up a fpq if we
1369 		 *	came here directly from _fp_ieee_exception,
1370 		 *	which is indicated by a zero fpu_qcnt.
1371 		 */
1372 		fp = lwptofpu(curthread->t_lwp);
1373 		utrapp = curthread->t_procp->p_utraps;
1374 		if (fp->fpu_qcnt == 0) {
1375 			inst = fetch_user_instr((caddr_t)rp->r_pc);
1376 			lwp->lwp_state = LWP_SYS;
1377 			pfpq = &fp->fpu_q->FQu.fpq;
1378 			pfpq->fpq_addr = (uint32_t *)rp->r_pc;
1379 			pfpq->fpq_instr = inst;
1380 			fp->fpu_qcnt = 1;
1381 			fp->fpu_q_entrysize = sizeof (struct fpq);
1382 #ifdef SF_V9_TABLE_28
1383 			/*
1384 			 * Spitfire and blackbird followed the SPARC V9 manual
1385 			 * paragraph 3 of section 5.1.7.9 FSR_current_exception
1386 			 * (cexc) for setting fsr.cexc bits on underflow and
1387 			 * overflow traps when the fsr.tem.inexact bit is set,
1388 			 * instead of following Table 28. Bugid 1263234.
1389 			 */
1390 			{
1391 				extern int spitfire_bb_fsr_bug;
1392 
1393 				if (spitfire_bb_fsr_bug &&
1394 				    (fp->fpu_fsr & FSR_TEM_NX)) {
1395 					if (((fp->fpu_fsr & FSR_TEM_OF) == 0) &&
1396 					    (fp->fpu_fsr & FSR_CEXC_OF)) {
1397 						fp->fpu_fsr &= ~FSR_CEXC_OF;
1398 						fp->fpu_fsr |= FSR_CEXC_NX;
1399 						_fp_write_pfsr(&fp->fpu_fsr);
1400 						siginfo.si_code = FPE_FLTRES;
1401 					}
1402 					if (((fp->fpu_fsr & FSR_TEM_UF) == 0) &&
1403 					    (fp->fpu_fsr & FSR_CEXC_UF)) {
1404 						fp->fpu_fsr &= ~FSR_CEXC_UF;
1405 						fp->fpu_fsr |= FSR_CEXC_NX;
1406 						_fp_write_pfsr(&fp->fpu_fsr);
1407 						siginfo.si_code = FPE_FLTRES;
1408 					}
1409 				}
1410 			}
1411 #endif /* SF_V9_TABLE_28 */
1412 			rp->r_pc = rp->r_npc;
1413 			rp->r_npc += 4;
1414 		} else if (utrapp && utrapp[UT_FP_EXCEPTION_IEEE_754]) {
1415 			/*
1416 			 * The user had a trap handler installed.  Jump to
1417 			 * the trap handler instead of signalling the process.
1418 			 */
1419 			rp->r_pc = (long)utrapp[UT_FP_EXCEPTION_IEEE_754];
1420 			rp->r_npc = rp->r_pc + 4;
1421 			break;
1422 		}
1423 		siginfo.si_signo = SIGFPE;
1424 		fault = FLTFPE;
1425 		break;
1426 
1427 	case T_DATA_EXCEPTION + T_USER:		/* user data access exception */
1428 		siginfo.si_signo = SIGSEGV;
1429 		fault = FLTBOUNDS;
1430 		break;
1431 
1432 	case T_LDDF_ALIGN + T_USER: /* 64 bit user lddfa alignment error */
1433 	case T_STDF_ALIGN + T_USER: /* 64 bit user stdfa alignment error */
1434 		alignfaults++;
1435 		lwp->lwp_state = LWP_SYS;
1436 		if (do_unaligned(rp, &badaddr) == SIMU_SUCCESS) {
1437 			rp->r_pc = rp->r_npc;
1438 			rp->r_npc += 4;
1439 			goto out;
1440 		}
1441 		fp = lwptofpu(curthread->t_lwp);
1442 		fp->fpu_qcnt = 0;
1443 		siginfo.si_signo = SIGSEGV;
1444 		siginfo.si_code = SEGV_MAPERR;
1445 		siginfo.si_addr = badaddr;
1446 		fault = FLTBOUNDS;
1447 		break;
1448 
1449 	case T_ALIGNMENT + T_USER:		/* user alignment error */
1450 		/*
1451 		 * If the user has to do unaligned references
1452 		 * the ugly stuff gets done here.
1453 		 * Only handles vanilla loads and stores.
1454 		 */
1455 		alignfaults++;
1456 		if (p->p_fixalignment) {
1457 			if (do_unaligned(rp, &badaddr) == SIMU_SUCCESS) {
1458 				rp->r_pc = rp->r_npc;
1459 				rp->r_npc += 4;
1460 				goto out;
1461 			}
1462 			siginfo.si_signo = SIGSEGV;
1463 			siginfo.si_code = SEGV_MAPERR;
1464 			siginfo.si_addr = badaddr;
1465 			fault = FLTBOUNDS;
1466 		} else {
1467 			siginfo.si_signo = SIGBUS;
1468 			siginfo.si_code = BUS_ADRALN;
1469 			if (rp->r_pc & 3) {	/* offending address, if pc */
1470 				siginfo.si_addr = (caddr_t)rp->r_pc;
1471 			} else {
1472 				if (calc_memaddr(rp, &badaddr) == SIMU_UNALIGN)
1473 					siginfo.si_addr = badaddr;
1474 				else
1475 					siginfo.si_addr = (caddr_t)rp->r_pc;
1476 			}
1477 			fault = FLTACCESS;
1478 		}
1479 		break;
1480 
1481 	case T_UNIMP_INSTR + T_USER:		/* illegal instruction fault */
1482 		siginfo.si_signo = SIGILL;
1483 		inst = fetch_user_instr((caddr_t)rp->r_pc);
1484 		op3 = (inst >> 19) & 0x3F;
1485 		if ((op3 == IOP_V8_STQFA) || (op3 == IOP_V8_STDFA))
1486 			siginfo.si_code = ILL_ILLADR;
1487 		else
1488 			siginfo.si_code = ILL_ILLTRP;
1489 		fault = FLTILL;
1490 		break;
1491 
1492 	default:
1493 		(void) die(type, rp, addr, 0);
1494 		/*NOTREACHED*/
1495 	}
1496 
1497 	/*
1498 	 * We can't get here from a system trap
1499 	 * Never restart any instruction which got here from an fp trap.
1500 	 */
1501 	ASSERT(type & T_USER);
1502 
1503 	trap_cleanup(rp, fault, &siginfo, 0);
1504 out:
1505 	trap_rtt();
1506 	(void) new_mstate(curthread, mstate);
1507 }
1508 
1509 void
1510 trap_rtt(void)
1511 {
1512 	klwp_id_t lwp = ttolwp(curthread);
1513 
1514 	/*
1515 	 * Restore register window if a debugger modified it.
1516 	 * Set up to perform a single-step if a debugger requested it.
1517 	 */
1518 	if (lwp->lwp_pcb.pcb_xregstat != XREGNONE)
1519 		xregrestore(lwp, 0);
1520 
1521 	/*
1522 	 * Set state to LWP_USER here so preempt won't give us a kernel
1523 	 * priority if it occurs after this point.  Call CL_TRAPRET() to
1524 	 * restore the user-level priority.
1525 	 *
1526 	 * It is important that no locks (other than spinlocks) be entered
1527 	 * after this point before returning to user mode (unless lwp_state
1528 	 * is set back to LWP_SYS).
1529 	 */
1530 	lwp->lwp_state = LWP_USER;
1531 	if (curthread->t_trapret) {
1532 		curthread->t_trapret = 0;
1533 		thread_lock(curthread);
1534 		CL_TRAPRET(curthread);
1535 		thread_unlock(curthread);
1536 	}
1537 	if (CPU->cpu_runrun)
1538 		preempt();
1539 	if (lwp->lwp_pcb.pcb_step != STEP_NONE)
1540 		prdostep();
1541 
1542 	TRACE_0(TR_FAC_TRAP, TR_C_TRAP_HANDLER_EXIT, "C_trap_handler_exit");
1543 }
1544 
1545 #define	IS_LDASI(o)	\
1546 	((o) == (uint32_t)0xC0C00000 || (o) == (uint32_t)0xC0800000 ||	\
1547 	(o) == (uint32_t)0xC1800000)
1548 #define	IS_IMM_ASI(i)	(((i) & 0x2000) == 0)
1549 #define	IS_ASINF(a)	(((a) & 0xF6) == 0x82)
1550 #define	IS_LDDA(i)	(((i) & 0xC1F80000) == 0xC0980000)
1551 
1552 static int
1553 nfload(struct regs *rp, int *instrp)
1554 {
1555 	uint_t	instr, asi, op3, rd;
1556 	size_t	len;
1557 	struct as *as;
1558 	caddr_t addr;
1559 	FPU_DREGS_TYPE zero;
1560 	extern int segnf_create();
1561 
1562 	if (USERMODE(rp->r_tstate))
1563 		instr = fetch_user_instr((caddr_t)rp->r_pc);
1564 	else
1565 		instr = *(int *)rp->r_pc;
1566 
1567 	if (instrp)
1568 		*instrp = instr;
1569 
1570 	op3 = (uint_t)(instr & 0xC1E00000);
1571 	if (!IS_LDASI(op3))
1572 		return (0);
1573 	if (IS_IMM_ASI(instr))
1574 		asi = (instr & 0x1FE0) >> 5;
1575 	else
1576 		asi = (uint_t)((rp->r_tstate >> TSTATE_ASI_SHIFT) &
1577 		    TSTATE_ASI_MASK);
1578 	if (!IS_ASINF(asi))
1579 		return (0);
1580 	if (calc_memaddr(rp, &addr) == SIMU_SUCCESS) {
1581 		len = 1;
1582 		as = USERMODE(rp->r_tstate) ? ttoproc(curthread)->p_as : &kas;
1583 		as_rangelock(as);
1584 		if (as_gap(as, len, &addr, &len, 0, addr) == 0)
1585 			(void) as_map(as, addr, len, segnf_create, NULL);
1586 		as_rangeunlock(as);
1587 	}
1588 	zero = 0;
1589 	rd = (instr >> 25) & 0x1f;
1590 	if (IS_FLOAT(instr)) {
1591 		uint_t dbflg = ((instr >> 19) & 3) == 3;
1592 
1593 		if (dbflg) {		/* clever v9 reg encoding */
1594 			if (rd & 1)
1595 				rd = (rd & 0x1e) | 0x20;
1596 			rd >>= 1;
1597 		}
1598 		if (fpu_exists) {
1599 			if (!(_fp_read_fprs() & FPRS_FEF))
1600 				fp_enable();
1601 
1602 			if (dbflg)
1603 				_fp_write_pdreg(&zero, rd);
1604 			else
1605 				_fp_write_pfreg((uint_t *)&zero, rd);
1606 		} else {
1607 			kfpu_t *fp = lwptofpu(curthread->t_lwp);
1608 
1609 			if (!fp->fpu_en)
1610 				fp_enable();
1611 
1612 			if (dbflg)
1613 				fp->fpu_fr.fpu_dregs[rd] = zero;
1614 			else
1615 				fp->fpu_fr.fpu_regs[rd] = 0;
1616 		}
1617 	} else {
1618 		(void) putreg(&zero, rp, rd, &addr);
1619 		if (IS_LDDA(instr))
1620 			(void) putreg(&zero, rp, rd + 1, &addr);
1621 	}
1622 	rp->r_pc = rp->r_npc;
1623 	rp->r_npc += 4;
1624 	return (1);
1625 }
1626 
1627 kmutex_t atomic_nc_mutex;
1628 
1629 /*
1630  * The following couple of routines are for userland drivers which
1631  * do atomics to noncached addresses.  This sort of worked on previous
1632  * platforms -- the operation really wasn't atomic, but it didn't generate
1633  * a trap as sun4u systems do.
1634  */
1635 static int
1636 swap_nc(struct regs *rp, int instr)
1637 {
1638 	uint64_t rdata, mdata;
1639 	caddr_t addr, badaddr;
1640 	uint_t tmp, rd;
1641 
1642 	(void) flush_user_windows_to_stack(NULL);
1643 	rd = (instr >> 25) & 0x1f;
1644 	if (calc_memaddr(rp, &addr) != SIMU_SUCCESS)
1645 		return (0);
1646 	if (getreg(rp, rd, &rdata, &badaddr))
1647 		return (0);
1648 	mutex_enter(&atomic_nc_mutex);
1649 	if (fuword32(addr, &tmp) == -1) {
1650 		mutex_exit(&atomic_nc_mutex);
1651 		return (0);
1652 	}
1653 	mdata = (u_longlong_t)tmp;
1654 	if (suword32(addr, (uint32_t)rdata) == -1) {
1655 		mutex_exit(&atomic_nc_mutex);
1656 		return (0);
1657 	}
1658 	(void) putreg(&mdata, rp, rd, &badaddr);
1659 	mutex_exit(&atomic_nc_mutex);
1660 	return (1);
1661 }
1662 
1663 static int
1664 ldstub_nc(struct regs *rp, int instr)
1665 {
1666 	uint64_t mdata;
1667 	caddr_t addr, badaddr;
1668 	uint_t rd;
1669 	uint8_t tmp;
1670 
1671 	(void) flush_user_windows_to_stack(NULL);
1672 	rd = (instr >> 25) & 0x1f;
1673 	if (calc_memaddr(rp, &addr) != SIMU_SUCCESS)
1674 		return (0);
1675 	mutex_enter(&atomic_nc_mutex);
1676 	if (fuword8(addr, &tmp) == -1) {
1677 		mutex_exit(&atomic_nc_mutex);
1678 		return (0);
1679 	}
1680 	mdata = (u_longlong_t)tmp;
1681 	if (suword8(addr, (uint8_t)0xff) == -1) {
1682 		mutex_exit(&atomic_nc_mutex);
1683 		return (0);
1684 	}
1685 	(void) putreg(&mdata, rp, rd, &badaddr);
1686 	mutex_exit(&atomic_nc_mutex);
1687 	return (1);
1688 }
1689 
1690 /*
1691  * This function helps instr_size() determine the operand size.
1692  * It is called for the extended ldda/stda asi's.
1693  */
1694 int
1695 extended_asi_size(int asi)
1696 {
1697 	switch (asi) {
1698 	case ASI_PST8_P:
1699 	case ASI_PST8_S:
1700 	case ASI_PST16_P:
1701 	case ASI_PST16_S:
1702 	case ASI_PST32_P:
1703 	case ASI_PST32_S:
1704 	case ASI_PST8_PL:
1705 	case ASI_PST8_SL:
1706 	case ASI_PST16_PL:
1707 	case ASI_PST16_SL:
1708 	case ASI_PST32_PL:
1709 	case ASI_PST32_SL:
1710 		return (8);
1711 	case ASI_FL8_P:
1712 	case ASI_FL8_S:
1713 	case ASI_FL8_PL:
1714 	case ASI_FL8_SL:
1715 		return (1);
1716 	case ASI_FL16_P:
1717 	case ASI_FL16_S:
1718 	case ASI_FL16_PL:
1719 	case ASI_FL16_SL:
1720 		return (2);
1721 	case ASI_BLK_P:
1722 	case ASI_BLK_S:
1723 	case ASI_BLK_PL:
1724 	case ASI_BLK_SL:
1725 	case ASI_BLK_COMMIT_P:
1726 	case ASI_BLK_COMMIT_S:
1727 		return (64);
1728 	}
1729 
1730 	return (0);
1731 }
1732 
1733 /*
1734  * Patch non-zero to disable preemption of threads in the kernel.
1735  */
1736 int IGNORE_KERNEL_PREEMPTION = 0;	/* XXX - delete this someday */
1737 
1738 struct kpreempt_cnts {	/* kernel preemption statistics */
1739 	int	kpc_idle;	/* executing idle thread */
1740 	int	kpc_intr;	/* executing interrupt thread */
1741 	int	kpc_clock;	/* executing clock thread */
1742 	int	kpc_blocked;	/* thread has blocked preemption (t_preempt) */
1743 	int	kpc_notonproc;	/* thread is surrendering processor */
1744 	int	kpc_inswtch;	/* thread has ratified scheduling decision */
1745 	int	kpc_prilevel;	/* processor interrupt level is too high */
1746 	int	kpc_apreempt;	/* asynchronous preemption */
1747 	int	kpc_spreempt;	/* synchronous preemption */
1748 }	kpreempt_cnts;
1749 
1750 /*
1751  * kernel preemption: forced rescheduling
1752  *	preempt the running kernel thread.
1753  */
1754 void
1755 kpreempt(int asyncspl)
1756 {
1757 	if (IGNORE_KERNEL_PREEMPTION) {
1758 		aston(CPU->cpu_dispthread);
1759 		return;
1760 	}
1761 	/*
1762 	 * Check that conditions are right for kernel preemption
1763 	 */
1764 	do {
1765 		if (curthread->t_preempt) {
1766 			/*
1767 			 * either a privileged thread (idle, panic, interrupt)
1768 			 *	or will check when t_preempt is lowered
1769 			 */
1770 			if (curthread->t_pri < 0)
1771 				kpreempt_cnts.kpc_idle++;
1772 			else if (curthread->t_flag & T_INTR_THREAD) {
1773 				kpreempt_cnts.kpc_intr++;
1774 				if (curthread->t_pil == CLOCK_LEVEL)
1775 					kpreempt_cnts.kpc_clock++;
1776 			} else
1777 				kpreempt_cnts.kpc_blocked++;
1778 			aston(CPU->cpu_dispthread);
1779 			return;
1780 		}
1781 		if (curthread->t_state != TS_ONPROC ||
1782 		    curthread->t_disp_queue != CPU->cpu_disp) {
1783 			/* this thread will be calling swtch() shortly */
1784 			kpreempt_cnts.kpc_notonproc++;
1785 			if (CPU->cpu_thread != CPU->cpu_dispthread) {
1786 				/* already in swtch(), force another */
1787 				kpreempt_cnts.kpc_inswtch++;
1788 				siron();
1789 			}
1790 			return;
1791 		}
1792 
1793 		if (((asyncspl != KPREEMPT_SYNC) ? spltoipl(asyncspl) :
1794 		    getpil()) >= DISP_LEVEL) {
1795 			/*
1796 			 * We can't preempt this thread if it is at
1797 			 * a PIL >= DISP_LEVEL since it may be holding
1798 			 * a spin lock (like sched_lock).
1799 			 */
1800 			siron();	/* check back later */
1801 			kpreempt_cnts.kpc_prilevel++;
1802 			return;
1803 		}
1804 
1805 		/*
1806 		 * block preemption so we don't have multiple preemptions
1807 		 * pending on the interrupt stack
1808 		 */
1809 		curthread->t_preempt++;
1810 		if (asyncspl != KPREEMPT_SYNC) {
1811 			splx(asyncspl);
1812 			kpreempt_cnts.kpc_apreempt++;
1813 		} else
1814 			kpreempt_cnts.kpc_spreempt++;
1815 
1816 		preempt();
1817 		curthread->t_preempt--;
1818 	} while (CPU->cpu_kprunrun);
1819 }
1820 
1821 static enum seg_rw
1822 get_accesstype(struct regs *rp)
1823 {
1824 	uint32_t instr;
1825 
1826 	if (USERMODE(rp->r_tstate))
1827 		instr = fetch_user_instr((caddr_t)rp->r_pc);
1828 	else
1829 		instr = *(uint32_t *)rp->r_pc;
1830 
1831 	if (IS_FLUSH(instr))
1832 		return (S_OTHER);
1833 
1834 	if (IS_STORE(instr))
1835 		return (S_WRITE);
1836 	else
1837 		return (S_READ);
1838 }
1839